But MOST (as I mentioned) are wi-fi. Just search on amazon for SDHC spycam and wifi spycam. The wifi's outnumber the SDHCs and the SDHCs have really really bad ratings. It's also easier to watch a real-time feed versus taking out an SDHC card putting it in a computer and going through hundreds of AVI files. It's why most spycams are wifi models.
Speaking of which, anyone know if in California it is against the law to record your SO in your own home without their knowledge? We have a wire-tapping privacy law here but I don't recall if it applies to your own home and members of your family.
Either way, it sounds to me like your wife is a good woman. When a woman is really mad, she will let you know. Just do what you're supposed to do (be a good husband and do your chores), and I'm sure everything will be alright.
